JP4552178B2 - Coil winding method and apparatus for superconducting power storage device (SMES) - Google Patents

Description

  The present invention relates to a winding method and apparatus for a coil for a superconducting power storage device (SMES).

  The present invention is a technology generated by the development of a superconducting power storage device (SMES), which is the latest technology, and relates to a method of winding a conductor in a coil shape for the purpose of minimizing the AC loss of the superconducting conductor. .

  Minimize AC loss of superconducting conductors used in coils in devices that can store energy as magnetism by passing a current through coiled superconducting conductors that have zero electrical resistance below the critical temperature. To this end, a method and apparatus for winding a conductor while twisting it are provided.

  The present invention focuses on the fact that the AC loss (coupling loss) is minimized when the magnetic field applied to the superconducting molded stranded wire inside the conductor is parallel to the stranded wire. If each of the conductors is wound while being twisted so that the pre-calculated magnetic field angle matches the conductor angle, the loss can be reduced.

  As an effect of the present invention, the AC loss (coupling loss) is minimized when the magnetic field applied to the superconducting molded strand inside the conductor is parallel to the strand. Therefore, if each conductor in the coil cross section is wound while being twisted so that the magnetic field angle calculated in advance matches the conductor angle, the loss can be reduced.

  The present invention provides a method and apparatus for winding a conductor while twisting it in a coil for the purpose of minimizing the AC loss of a superconducting conductor used in a superconducting power storage device (SMES). Hereinafter, the present invention will be described in more detail with reference to embodiments. Of course, the present invention is not limited to the following embodiments.

  A superconducting power storage device (SMES) is a device that can store energy as magnetism by passing a current through a superconducting conductor that has a resistance of zero below a critical temperature in a coil shape. By connecting this device to the power system of the user facility, a high-grade new power supply system for measures against instantaneous voltage drop that can cover the entire facility is constructed.

  The present invention relates to a method and an apparatus for winding a superconducting conductor used in the superconducting power storage device (SMES) into a coil while twisting, and this is a method for minimizing the AC loss of the superconducting conductor. This is because it is considered necessary to wind the conductor while twisting it.

  Since SMES coils are required to be reliable and easy to handle, it is desirable to select a conduction-cooled pulse coil system using a low-temperature superconducting conductor. However, since this method cannot perform cooling depending on the high specific heat of helium, a superconducting conductor that reduces the AC loss of the conductor and suppresses the increase in the conductor temperature is required. As a conductor to be used, an NbTi / Cu molded stranded wire extruded with aluminum can be used.

Since the coil winding needs to be performed while twisting the conductor for the above-described reason, the groove 2 as shown in FIG. 1 is provided in the longitudinal direction of the conductor so that the twist angle can be discriminated from the appearance of the conductor. It is possible to achieve both mechanical strength and thermal conductivity by alternately arranging strand-insulated copper stranded wires (Litz wires) and spacers (manufactured by Dyneema) to ensure high thermal conductivity in the coil.

  From the above, the winding machine required to wind the SMES coil twists the superconducting conductor with a cross section with an accuracy of ± 5 degrees in preparation for the force generated when the electric power stored in the coil is taken out. However, it is necessary to keep the tension of about 1000N.

FIG. 2 is a schematic view showing an embodiment of the present invention. The winding unit 4 has a winding motor and a traverse motor for winding the conductor in a coil shape, and the twisting unit 6 has a tension detector for detecting a tension of 1000 N and an intermediate shaft motor for controlling the tension. 8, unwinding motors for keeping the unwinding tension constant are respectively installed, and motors are respectively installed in the twisting part 6 and the unwinding part 8 for twisting the conductor. In addition, a proximity sensor 10 for detecting the twist angle θ of the conductor is installed between the winding portion 4 and the twist portion 6. The proximity sensor 10 is rotated along the outer periphery of the conductor as shown in FIG. 1 by the driving motor, and the twist of the conductor is detected by detecting the groove 2 continuously provided in the conductor longitudinal direction of the outer periphery of the conductor. The angle θ is detected.

  If the wound coil has 27 turns, it will be 14 layers, and 48 spacers and litz wires will be inserted between each layer. At present, since they are manually inserted, it is necessary to wind the winding work intermittently after each layer is wound. The total number of spacers and litz wires is about 1400.

  Even when the winding operation is interrupted as described above, it is necessary to always maintain a tension of 1000 N. For this reason, PLC (Programmable Logic Controllcr) is used for control of each servo motor. Among the motors to be controlled, the winding, intermediate and unwinding motors need to be torque controlled. When a pulse train is input to the motor driver, positioning is performed. When an analog signal is applied, the motor driver rotates with a torque corresponding to the voltage.

  Since each motor is selected with an electromagnetic brake to maintain the tension when stopped, it is necessary to control the brake. In order to know the rotation position of each motor, the signal of the rotary encoder is taken in and the traversing motor is controlled according to the rotation angle. Interlocks such as emergency stop switch and motor torque / speed limit must be performed strictly because the output of each motor is relatively large and damage due to malfunction is a concern.

  When the magnetic field applied to the superconducting molded strand inside the conductor is parallel to the strand, the AC loss (coupling loss) is minimized. Therefore, if each conductor in the coil cross section is wound while being twisted so that the magnetic field angle calculated in advance matches the conductor angle θ shown in FIG. 1, the loss can be reduced. The magnetic field angle calculated in advance is given as numerical data.

  A twist angle detection / control unit as shown in Fig. 3 is provided in front of the winding part that winds the conductor around the coil winding frame, and when twisting the conductor, the pulley 12 in front of the winding part is fixed and the intermediate shaft 14 is rotated. And twist the conductor. The conductor angle between the two pulleys can be obtained by linearly approximating the conductor angle at two locations measured by the proximity sensor 10.

The control procedure when winding while twisting the conductor is shown below.
(1) Two conductor angles are measured using a proximity sensor, and an angle function before twisting is obtained.
(2) Obtain the rotation angle of the intermediate shaft.
(3) The intermediate shaft is rotated using the obtained rotation angle, and the conductor is twisted.
(4) Send the conductor by the specified interval and perform winding.
In the above operation, the operation command based on the calculation result by the personal computer is given to the PLC.
Winding work is carried out while repeatedly performing twist winding control.

  The present invention relates to a winding method and apparatus for winding a conductor while twisting it in a coil shape, and various control devices are used for winding, and the tension, twist angle, etc. of the conductor are strictly controlled. It is what is done. Accordingly, it is possible to widely provide a twisted material with very few twist spots, a stranded wire with very few twist spots, and the like.

Schematic diagram of conductor Schematic of winding device Schematic diagram of twist control unit

Explanation of symbols

2 groove 4 winding part 6 twisting part 8 unwinding part 10 proximity sensor 12 pulley in front of winding part 14 intermediate shaft θ conductor twisting angle

Claims (1)

The winding portion 4, the twist portion 6 for twisting the conductor, and the unwinding portion 8 that inclines in synchronization with the twisting portion 6, and the conductor is fed by rotating the twisting portion 6 and the unwinding portion 8. Is a winding method of a coil wound around the winding portion 4 in a state where the conductor is twisted. The winding portion 4 includes a winding motor and a traversing motor for winding the conductor, and the twisting portion 6 includes A tension detector for detecting a tension of 1000 N, an intermediate shaft motor for controlling the tension, a winding motor for keeping the winding tension constant in the winding section 8, and a twisting section 6 for twisting the conductor. In addition, a motor is installed in each of the unwinding portions 8, and a proximity sensor 10 for detecting the twist angle θ of the conductor is installed between the winding portion 4 and the twisting portion 6. Turn along the outer circumference of the conductor. Is allowed, the winding method of SMES coil, characterized in that detecting the twist angle θ of the conductor by detecting a groove 2 provided continuously to the conductor longitudinal direction of the conductor circumference.

Images